Recovering the vapors of varnishes and the like



D. LARKI N Jan. 14, 1930.

RECOvERING THE VAPORS OF' VARNISHES AND THE LIKE 4l sheets-sheet 1 FiledMarch 13, 1925 mm Q E LT Jan. 14, 1930. D. LARKIN 1,743,554

RECOVERING THE VAPORS OF VARNISHES AND THE LIKE Filed Makrch l5, 1925 4Sheets-Sheet 2 Ihm Jam. 14, 1930. D, LARKIN 1,743,554

RECOVERING THE VAPORS OF VARNISHES AND THE LIKE Filed March 15, 1925 4Sheets-Sheet 5 l 1 a .lg f

il, ff@ ,7

ttozneq 1 Jan. 14, 1930. D. LARKIN 1,743,554

- RECOVERING THE VAPORS OF VARNISHES AND THE LIKE Filed March 13, 1925 4Sheets-Sheet 4 Patented Jan. 14, 1930 UNITED lSTATES PATENT CFFICE DAVIDLARKIN, F ST. LOIS, MISSOURI RGOVERING THE VAPORS OFVARNISHES AND THELIKE Application filed March 13, 1925.' Serial No. 15,376.

This invention relates to a process of and apparatus for recovering thevolatile constituents of varnishes andthe like Which have associatedWith the varnish industry; but it is also of great economicyirnportancefor the reason that the high-costbf the materials recovered is animportant desideratum in the manufacture of varnishes.

Briefly described, the process consists in subjecting thevapor-chargedair to a'precipitating agent or fluid Whose specificgravity diers from that of the volatile constituents of the varnish, orWhich is not miscible therewith, and then separating the precipitant andthe precipitate in a manner which depends for its functioning on thefact that the precipitant and precipitate do not mix or have diferentspeciic gravities. ing out the process comprises, briefly, aprecipitating means employing a liquid precipitant, means for producinga flow of the vapor-laden air in intimate contact with the matic meansare also provided for returning -the -spent spraying' liquid to thespraying y means. The invention also resides in certain The apparatusfor carryi desirable features and details of construction which will belhereinafter pointed out.

In the accompanying drawings forming part of this specification, inwhich like numbers of reference denote like parts Whereever they occur,

Figure l is an elevational view of the complete apparatus of thisinvention;

Figure 2 is a plan view of the same; Figure 3 is a detail sectional viewthrough one of the spray nozzle holders;

Figure 4: is a fragmentary view of the entrance end of the apparatus; i

Figure 5 is a view of the exit end of the apparatus;

Figure 6 is a detail transverse sectional view through one of the sightopenings in the casing;

j Figure 7 is a longitudinal vertical sectional View through theapparatus; and I Figures 8, 9, and' 10 are vertical transverse sectionalviews takeh on the lines 8 8, 9 9, and 10-10 respectively in Figure 7,Figure 10 being partly broken away.

Referring now in detail to the preferred embodiment of this inventionillustrated in thesaid-drawings, the tank 1 is preferably elevated atrasuitable height by mounting the same on a suitable frame basestructure2. The .tank 1 is substantially rectangular in form, andcomprisesfour sides 3, 4, 5, and 6 and a bottom 7, the top being open. Ahorizontal flange 8 is disposed preferably around the interiordof thetank a short distance from the to the said flange preferably being apart of) an angle ironv 9, riveted or secured in any common manner tothe sides 3, 4, 5, and V6.. A casing 10, built up of outer Wall sec-.tions 11, partitions 12 and 13, and top sections 14 riveted o r`secured together in any tank 1, so-that the lower edges of the outerIWall sections 11 and partitions 12 and 13 lie .suitble Huid tightmanner, ts Within the below the normal level of the liquid 'to be placedinthe tank 1. Flanges 15, formed onthe lower end of the outer wallsections 11, are

adapted to rest on the flange 8, so that the constituents of the varnishoccurs, and in the through a bend35.

casing 10 is maintained in proper vertical relation to the tank 1. Thesaid flanges 8 and 15 may be secured together by bolts 16. Sightopenings 17 in the walls 11, preferably in the formof fluid tight glasswindows 'enable the operator to view the interior of the casing from theoutside, and to observe the manner in which the apparatus is functioningon the inside. The opening 17, shown in detail in Figure 6, comprisesexternally threaded annular casing 18, internally threaded ring 19 forclamping the same to casing 10, internally threaded flanged ring 2O forclamping plate glass 21 to casino 18, washer 22, and packing rings 23and 24. Each of the partitions 12 have openings 25 in the upper portionsthereof; and each of the partitions 13 have similar openings 26y in thelower portions thereof, the level of the liquid in the tank 1 preferablyintersecting the openings 26. The partitions 12 are disposed alternatelywith the partitions 13, dividing the casing 10 into a row of alternateuptake and downtake compartments or chambers 27, 28, 29, 30 and 31, bestshown in Figures 7 to 10 inclusive. 4

A downtake pipe 32 is juxtaposed to the entrance end of the apparatus,and leads through an opening 33 in the lower portionl of the front endwall of the casing 10 into' the chamber 27. Means are provided to lead'vapor-charged air from those portions of the plant where the evaporationof' the volatile present instance such means consists of a pipe 34leading from a varnish room on the floor below into the upper end of thepipe 32, pref# erably transversely into the side thereof In the pipe 32disposed oppositely to the bend 35, is a door 36, which provides accessto the interior of the pipe and to spraying means therein to behereinafter described. A pipe 37 leads from the upper portion of chamber31 through the exit end or rear wall of the casing 10 down to a blower38, and from the blower 38 a pipe 39 leads to the exterior of thebuilding.

pipe 32 and in the casing 10`Yare supplied with suitable sprayingliquid, preferably water',

`through a suitable system of piping and of-V any suitable pumpingmeans. lVater is sup` plied to the system of piping from any suita valve42 to T-fitting 43, included in the `circulating system now to bedescribed.- One end of T-fitting 43 leads to the first stage unit 44 ofa two-stage centrifugal pump 45, and a pipe 46 leads from the firststage unit 44 to the second stage unit 47, from vwhencepipe 48 rises tothree-way valve 49, from or cleansing by mere The spraying means in thedowntake air vnipples 54 and 55 to three-way valve 56. De-

livery pipe 57 leads from valve 56 to T-fitting 58, from which leadbranchpipes 59 and 60. Branch' pipe 60 leads to header 61, disposedabove the casing 10, and supplying branches 62, each of which leadsthrough a union 63 and elbow 64 to a spray nozzle 65, as shown in detailin Figure 3. The lower end of elbow 64 enlarges laterally in to atransverse annular flange 66, having a seat 67, adapted to co-operatewith a seat 68 `on the upper end 0f.an externally threaded sleeve 69,the lower end of which spreads into a flange 70, adapted to -be clampedagainst the under side of the top-walls 14 of the casing 10 by means ofa clamping ring 71, threading on the sleeve 69 against the upper side ofthe top walls 14.

rElbow 64 is clamped to sleeve 69 by means of clamping ring 7 2, screwedn the sleeve 69 so that flange 73 of the ring 72 bears againstconstruction for holding the spray nozzles, the latter may be readilyremoved for the purpose of inspection repairs, replacement,

ly unscrewing ring 72 and union 63, and without disturbing ordisconnectingthe remainder ofthe piping. This means for holding thespray nozzle forms the subject-matter of another application for patentby the same inventor. In the present instance two spray nozzles havebeen provided for each ofthe chambers 27, 28, 29, and 30, but anysuitable number may be employed therein according to requirements.Branch pipe 59 leads to a point over the upper end wall 74 lof downtakeair-pipe 32, and. kthen descends through wall 74 into pipe 32 to a pointpreferably slightly lower than the bottom of the opening leading intothe elbow 35. Pipe 32 passes through and vis securely held by a tightlyfitting flange 75 secured to the wall 74. A vspray nozzle 76 is-securedto the terminusof pipe 59 in the pipe 32.v yThe spray nozzle 76 ispreferably 'much vlarger 'than the nozzles 65, and also functions as aninjector to assist the downward flow of air in the pipe 3.2. A pressureindicator 77 may be secured to the delivery pipe 57 preferably lat apoint a`short distance above the `threeway valve 56. 'A dischargeopening 78.r is

formed in the bottom 7 of the tankl, preferably ata point under thechamber .3.1. A

pipe 7 9 is connected to the said opening 78 by means ofa flange,80,mand, descends to a T-fitting 81, from which branch pipes n82 and 83lead to the waste receiver and T-fitting 43 respectively. Pipes 82 and83 contain respective gate valves 84 and 85by means of which the waterdischargedfrom the tank 1 may be diverted either to the pump 45 orthewaste pipe 82. l` Y .Y -f

Centrifugal' pump 45 is mounted on its base 86, which also bearsstandards 87, in which is journaled the pump operating shaft 88, drivenby means of pulley 89, affixed thereL to. Frame 90 of blower 38 includesbearings 91, in which is journaled blower operating shaft 92, driven bypulley 93, aflixed thereto. Pulleys 89 and 93 are driven by belts 94 and95, respectively, which are in turn driven by respective pulleys 96 and97v disposed at opposite ends of the driving motor 98.

Chamber l31 is provided for the purpose of removing as much as possibleof the residue of vapor remaining in the air after the latter has passedthrough the spraying chambers 27 28, 29, and 30. The means for removingthe residuum of vapor comprises a plurality of baffle plates 99,arranged in staggered relation on opposite sides of the chamber 31, soas to provide atortuous path for theY- air ascendingtherethrough. Thesaid baffles are secured respectively to partition wall 13 and end walll1 by means of rivets, or in any other common manner, so as to slopedownwardly from the walls. Flanges 100 extend upwardly from the loweredges 101 of the said batlies to prevent condensed vapor which hascollected on the baflles from draining directly ofil the edges 101. Oneend 102 of each of the edgesA 101 is lower than the other, so that allthe condensed vapor collected on the baffles 99 must drain oit at asingle point, that is, at the lower end 102 of the edge 101. By thusdraining olf at a .t ringle concentrated point, the condensed vapor isnot so apt to be re-atomized as it might be were it allowed to drain ofi-along an extended edge or at a plurality of points. Furthermore,arranging the lower end 102 adjacent the side wall ofthe chamber causesthe condensation to flow down along the wall in a continuous streaminstead of breaking up into drops, thus further preventing're;atomization.

The varnish vapor condensed in thecham- (bers 27 28,29, 30, and 31,together with the spent sprayingwater from the several nozzles, settlesinto the tank 1 vin layers of two different liquids, which do not `mixand have different specific gravities, thelighter layer 103 of condensedvarnish vapor oating on .top of the heavier layer 104 of water. Theupper layer drains off into overfl'ow pipes 105, rising vertically fromthe overflow header 106, which extends entirely through the tank 1 fromend to end,and is secured in position in the tank 1 by means of fluidtight flanges 107 secured to the end walls 3 andE respectively. Theoverflow risers 105 ex 'and high enough to maintain the level of liquidin the tank at a sufficient height to seal the open bottom of thecasing10 and yet not cause any flow over the edges of Athe tank 1. Thatportion of the pipe 106 emerging` from the endwall .5 leads through atrap 108 to a depending terminus 109, from whence it discharges into anysuitable receptacle that may be placed thereunder. Overflow risers 105,header 106, trap 108, and discharge stem` by a manhole 112, in the end3, and normallyy closed by a cover 113, secured thereto by screws 114. Abaii'e plate 115 is secured in any suitable manner to the sides 4 and 6of the tank 1 directly over the discharge opening 78.

The said baie 115 prevents the formation of a whirlpool over thedischarge opening 78, which whirlpool would draw into the open-y ing 78the upper layer of varnish constituents as well as the lower layer ofwater, thus frustrating the purpose of the apparatus. be noted that bothopening 78 and overflow pipe 105 are juxtaposed to the end wall 5 of thetank l, so that both upper and lower lay- Jers flow in the samedirection through the tank 1 and also with the stream of air as itprogresses through chambers 27, 28, 29, 30, and 31. A riser 116, leadingfrom the tank 1 through a flange 117 on the side 4, enables theoperatorio observe the level of liquid in the tank through its openupper end. Or the riser may be formed of glass tubing to facilitate theobservation.A

The mode of operation of this apparatus will now be briefly described.The motor 98 is started, operating the blower 38 and pump 45, and thusproducing acirculation of water towards the spray nozzles and 76, anddrawing in vapor-charged air through pipe 34 into downtake pipe 32,lwherein it descends and passes through opening 33 into chamber 27,ascending therein and emerging therefrom through openings 25 inpartition 12 into downtake chamber 28. The

It willy air then descends in chamber 28, passes l .through openings 26in partition 13 into chamber 29. Inlike manner, the air ascends in.chamber 29, descends in chamber` 30, and ascends again in chamber 31,from whence it issues into ,exit p'pe 37 to the blower 38,' and from thelatter through pipe 39 into the outside'atmospfhere. The spray issuing Inozzles, settles into the tank 1, Ithe precipi,

tate of varnish constituents floating on a sublayer of water. Theoverflow pipes 105 and discharge opening 78 form selective means fordiverting the precipitate and precipitant into separate channels, thevarnish ingredients being delivered to discharge spout 109, and thewater being returned to the pump 45.

Having thus fully described this invention, I hereby reserve the benefitof all changes in form, arrangementyorder, or use of parts, as it isevident that many minor changes may be made therein without departingfrom the s irit of vthis invention or the scope of the ollowing claims.Y

I claim:

1. Apparatus for recovering the volatile varnish constituents fromvarnish-laden atmosphere comprising a casing, spaced vertical partitionwalls located within the casing, the alternating partition walls havingopenings at the lower ends and the intervening partition wall having anopening at its upper end, vertically disposed 'overivow pipes passingthrough the bottom wall of the casing and located between the partit-ion`walls and vertically disposed spray nozzles passing lthrough the topwall of the casing and having their disch-arge ends in spaced parallelrelation with the intake ends of the overiow pipes,- the nozzles and theoverfiow pipes lying in the-same vertical plane and located midwaybetween the partitions, the arrangement being such that a volume ofvarnish laden atmosphere when passed throughthe casing is folded intoparallel columns by the vertical partition walls, said columnshavingcurrents moving diagonally through the spaces between the nozzlesand the overflow pipes, and simultaneously precipitating jets areinjected medially into the columns and directed downwardly toward theintake ends 'of the overflow pipes in lines at angles to the movement ofsaid currents.

2. Apparatus for recovering the volatile varnish constituents fromvarnish-laden atmosphere comprising a casing, spaced vertical partitionwalls located within the casing, t-he alternating partition walls havingopenings at the lower ends and the intervening partition wall having anopening at its upper end, vertically disposed overflow pipes passingthrough the bottom wall of the casing and located between the partitionwalls, and having their receiving end edges located i a plane lyingbelow the plane in which they pipes lying in the same vertical plane andlocated-m1dway between the partitions7 the arrangement being such that avolume `of columns and directed downwardly toward V the intake ends ofthe overow pipes in lines at angles to the movem nt of said currents.

In testimony whereo I hereunto aix my signature.

\ DAVID LARKIN.

